/*
 * Copyright 2011 The Rusted Roof, LLC.
 *
 *    Licensed under the Apache License, Version 2.0 (the "License");
 *    you may not use this file except in compliance with the License.
 *    You may obtain a copy of the License at
 *
 *        http://www.apache.org/licenses/LICENSE-2.0
 *
 *    Unless required by applicable law or agreed to in writing, software
 *    distributed under the License is distributed on an "AS IS" BASIS,
 *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *    See the License for the specific language governing permissions and
 *    limitations under the License.
 */

package org.proteusframework.platformservice.grammar.expression;


/**
 * A basic class for binary expressions, that is expressions having a left member and a right member
 * which are in turn expressions.
 */
public abstract class BinaryExpression implements IExpression
{
    private IExpression leftExpression;
    private IExpression rightExpression;
    private boolean not = false;

    public BinaryExpression()
    {
    }


    public IExpression getLeftExpression()
    {
        return leftExpression;
    }

    public IExpression getRightExpression()
    {
        return rightExpression;
    }

    public void setLeftExpression(IExpression expression)
    {
        leftExpression = expression;
    }

    public void setRightExpression(IExpression expression)
    {
        rightExpression = expression;
    }

    public void setNot()
    {
        not = true;
    }

    public boolean isNot()
    {
        return not;
    }

    public String toString()
    {
        return (not ? "NOT " : "") + getLeftExpression() + " " + getStringExpression() + " " + getRightExpression();
    }

    public abstract String getStringExpression();

}
